Warning: SPOILERS ahead for Venom
Venom (re)introduces viewers to a powerful alien race of so-called "symbiotes." These strange creatures bond with other living beings, drawing sustenance from them and even taking control of them. They're one of the creepiest, most sinister ideas in the Spider-Man franchise - one that really isn't traditionally associated with sci-fi body horror.
Director Ruben Fleischer is a comic book fan, and he grew up loving the Venom books. As a result, he's taken a remarkably comic-book-accurate approach when it comes to adapting the slithering symbiotes for the big screen. Venom is filled with concepts and ideas lifted straight from the comics, including when it comes to establishing the nature and actions of the symbiotes themselves.
Related: Venom: The 10 Biggest Spoilers
Here, we'll take a brief look at everything you need to know about the symbiotes of Venom. What are the symbiotes, where do they come from, what are they capable of, and just why are they here?
The Origin of the Symbiotes in Venom
The symbiotes originated from the planet Klyntar (confirmed as canon to the film by an official tie-in comic), and they evolved to exist in a symbiotic relationship with other life-forms. In truth, however much the Klyntars may dislike admitting it, they tread a fine line between between symbiotes and parasites; as we see in Venom, the bodies of most hosts are unable to sustain the symbiotes for long, and the experience of carrying a symbiote can be fatal to the host as their organs fail under the strain. True symbiosis appears to only be possible if the host ingests enough sustenance to keep their body running during the first few hours after they bond with the symbiote. The symbiotes drive the host to crave two types of food; live meat (such as a lobster, or a thug's head), or raw meat (such as gone-off chicken).
In Venom, the symbiotes detected plentiful life on Earth and launched their version of an exploratory vessel to get them here. That's the "comet" discovered by the Life Foundation, and it's home to millions of symbiotes - essentially an invasion force. It's reasonable to assume that the symbiotes have consumed all life on their homeworld, and are now branching out; the creatures can clearly exist in stasis when not in an oxygenated environment, so it's unclear how long they've been traveling. If the comet showed no signs of being artificial, then it could well have been traveling between the stars on kinetic force alone - possibly even for billions of years.
Introducing the Symbiotes of Venom
According to Venom, the four symbiotes picked up by the Life Foundation are essentially a team, with different ranks and different capabilities. Two of the symbiotes die during the Life Foundation's experiments, and although they aren't named in the film itself, their distinctive colorschemes will be recognizable to anyone who's read the comics. The blue one is Toxin, and the yellow one is either Phage or Scream. These are tremendously powerful beings in their own rights back in the comics, so it's something of a shame we never see what they're capable of.
Only two symbiotes play a major part in Venom: Riot and Venom himslf. The former is apparently the team leader, and he possesses powers that far outstrip Venom's. Riot's will appears to be stronger, and so he takes full control of the host as soon as he establishes contact - something that's chillingly visible in the way he jumps from host to host. When Riot transforms into his full symbiote form, he can manipulate it in any way he chooses, forming a variety of devastating weapons. Incredibly, he's even able to sacrifice a part of his own being by forming projectile spikes, or blades that he leaves embedded within his victims. Presumably this means that he draws upon the host body's life force in order to regenerate his own symbiote.
Judged against Riot, Venom is far more prosaic. He doesn't appear to have the will to overthrow his host's mind, instead sharing it and attempting to relate to the host. He's strong, fast, and agile - but nowhere near Riot's level. While he can project symbiotic tendrils that are tremendously powerful (they can rip doors off cars with ease) he seems unable to morph into the variety of forms we see Riot take on. Where Riot is a team leader, Venom is a basic "grunt," nothing special among his own people. That's why he's willing to give humanity a chance; he sees an opportunity to be something greater.